#include "stdio.h"
#include "string.h"

int main(){
    int alphabetic(char);
    int longest(char []);
    int i;
    char line[100];
    gets(line);
    for(i=longest(line);alphabetic(line[i]);i++){
        printf("%c",line[i]);
    }
    return 0;
}

int alphabetic(char c){
    if((c>='a'&&c<='z')||(c>='A'&&c<='Z')) return 1;
    else return 0;
}
int longest(char string[]){
    int len=0,i,length=0,flag=1,place=0,point;
    for(i=0;i<=strlen(string);i++){
        if(alphabetic(string[i])){
            if(flag){
                point=i;
                flag=0;
            } else{
                len++;
            }
        } else{
            flag=1;
            if(len>=length){
                length=len;
                place=point;
                len=0;
            }
        }
    }
    return place;
}